


Nothing Lasts Forever

by fuladaris



Category: Naruto
Genre: Alzheimer's Disease, Found Family, Hurt/Comfort, Immortality, Jashin tag is there if that's how you interpret the voice Hidan hears at the end, Jashinism, M/M, Originally Posted on Tumblr, Suicidal Thoughts, Swearing, Team as Family, but it could be any of the other Akatsuki members too, since he himself speculates it, up to you!! I had no one specific in mind
Language: English
Status: Completed
Published: 2021-01-21
Updated: 2021-01-21
Packaged: 2021-03-12 13:34:08
Rating: Mature
Warnings: Major Character Death
Chapters: 1
Words: 3,057
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/28886172
Author URL: https://archiveofourown.org/users/fuladaris/pseuds/fuladaris
Summary: Kakuzu takes the diagnosis better than Hidan does. In fact, while Hidan demands to know why there isn’t a cure, threatens and cajoles and curses and clutches his rosary, Kakuzu - says nothing at all.
Relationships: Hidan/Kakuzu (Naruto)
Comments: 22
Kudos: 67





	Nothing Lasts Forever

**Author's Note:**

> I posted this on one of my tumblr blogs as well - I reblogged a writing prompt about immortal beings as old as time with Alzheimer's, a friend sent an ask about Kakuhida dealing with Alzheimer's, I started researching the disease and found out financial difficulty is one of the earliest signs, and it turned into this. A (different) friend whose relative had Alzheimer's said it was accurate, so between that and the research, I hope it is!

Kakuzu overpaid. That was the start of it all. 

He wasn’t the kind of man who was  _ ever  _ given change. He paid the  _ exact  _ amount,  **_ every single time _ ** , and so Hidan’s brow furrowed in confusion when the cashier handed Kakuzu some money back - as, of course, did Kakuzu’s.

“I paid exact,” he says (and Hidan had noticed  _ this  _ about Kakuzu, too - the man, for all his moneygrubbing,  _ never  _ stilted little mom and pops like this one. It was kind of honorable, actually, that he  _ wouldn’t  _ quietly pocket the extra change if the person giving it to him might need it more). 

“No, sir, you gave me an extra couple of coins.”

“I - did?”

“Yes, sir!”

Wordlessly, stunned, Kakuzu takes his change, and Hidan teases him about it when they leave (”Forget how to count, big guy?”) - but they both think nothing of it, after a minute.

***

Three months later, Kakuzu swears and tries to strangle Hidan, who is attempting to flip through Kakuzu’s meticulously kept bank book.

“Would you GIVE IT A REST, old man?” the younger man snaps, attempting with some difficulty to fend off his partner. “I’m telling you, I didn’t steal any of your fucking money. You probably made a mistake, that’s all!”

“I don’t make  _ mistakes _ , Hidan-”

“Well,  _ clearly  _ you did, and if you’d quit losing your fucking mind for two damn minutes-” ( _ oh, how he would come to regret saying that _ ) “-maybe I could find it! Math isn’t my  _ specialty _ , but I ain’t  _ hopeless  _ at it-”

“There isn’t a  _ mistake  _ to  _ find _ , you little-”

“A-HA! There! See?! It wasn’t balanced properly!” Triumphant both for having gotten one over on Kakuzu and for having proven himself at least  _ marginally  _ financially capable, Hidan thrusts the book into his partner’s face, tapping on one of the lines. “Your math is off, man. That’s all. Now would you let go of me?!”

Kakuzu does  _ not  _ let go until he’s reviewed the lines in question for himself - at which point, he sinks, stunned once again, onto the bed. “How did I...?”

“Dunno, ‘Kuzu,” Hidan hums, remarkably chipper for a man who’d just been choked (but, then again, given his immortality, Kakuzu could have slit Hidan’s throat and Hidan would have been no worse for wear). In fact, he sits next to Kakuzu and slings an arm around his shoulders -  _ clearly _ , Hidan harbors no ill will. “Even a broken clock is wrong twice a day, so-”

“One, if you call me Kuzu again, I’ll go back to choking you; two, the expression is  _ right  _ twice a day; three, I don’t make banking mistakes, you  _ know  _ that; and four,” Kakuzu grumbles, leaning into the hold, “I’m sorry I accused you of stealing from me. I just can’t believe I...”

“Ha! There’s a first time for everything, buddy.  _ Including  _ the apology.” Grinning, Hidan gives him a kiss on the cheek - there really  _ aren’t  _ any hard feelings, and to prove it further, he puts Kakuzu’s hand on his neck again and purrs, “Kuzu.”

***

“What do you  _ mean  _ you can’t remember where you put it?” Hidan asks, eyes wide with shock, for he’d never seen Kakuzu misplace a  _ penny _ , let alone his  _ whole wallet _ .

“Exactly what I said!” Kakuzu hisses back, his own eyes equally wide - albeit with panic, rather than surprise - as he empties his bag on the ground. “It’s not  _ in here _ .”

“It- It has to be. It’s as important to you as your fucking hearts, so-.” 

“Do  **_ you  _ ** see it?”

“Well, no, but - look, the inn is right up the road, so I’ll just go back and see if we left it in the room, all right? You look through my stuff, too,” Hidan adds, tossing his own travel bag down on the ground, “and I’ll go ask the chick at the front desk.”

His objective declared, Hidan heads back to the inn - which is  _ exactly  _ where he finds Kakuzu’s wallet.

***

Hidan notices it a lot more, after that, and it disturbs him.

Memory lapses. Confusion. Mistakes. Things that did not suit Kakuzu.

They’re cuddling in a different inn, a rare moment of tender, domestic intimacy between two men who preferred their lives volatile and violent, and Hidan reaches up to brush back his partner’s hair.

“Hey, you feeling okay, Kakuzu?” he asks, softly.

“Just fine, why?” Indeed, Kakuzu’s voice is the kind of low, satisfied rumble Hidan seldom gets to hear when they’re on the move, but that indicates that the older man is - for once -  _ blissfully  _ happy. 

(Hidan almost hates to keep going - but he knows he  _ has  _ to, lest he not get another chance.)

“You seem kind of - forgetful, lately? Like, that’s more  _ my  _ thing,” Hidan tries to joke, but it falls flat, and he adds awkwardly, “I’m just wondering if something’s on your mind, or whatever.”

Kakuzu doesn’t respond, for a long while, and Hidan doesn’t like that. 

And then, Kakuzu whispers, “I’ve been thinking that, perhaps, my age is catching up with me,” and Hidan  _ really  _ doesn’t like  _ that _ .

“No. No, fuck you.” Hidan shoots out of Kakuzu’s grip, ignoring the hurt look that flashes in those green-red eyes. “That can’t happen. You ain’t supposed to  _ age _ , asshole. What’s the point of collecting hearts and shit if it doesn’t stop you from ageing?”

“It hasn’t  _ stopped  _ my ageing, Hidan. It’s  _ slowed it down _ . There’s a  _ difference _ .”

“Well, there shouldn’t  _ be  _ a difference, because  **_ you’re not supposed to age _ ** . You’re supposed to spend  _ eternity  _ with me, remember?” There’s a catch in Hidan’s voice, and it’s a sound Kakuzu’s never heard from the younger man before.

“I have no intention of leaving you,” Kakuzu murmurs, reaching out - a placating gesture, or an attempt at one. “Come here, Hidan.” 

Hidan doesn’t, and Kakuzu sighs, sits up, holds his arms out again. “I  _ promise  _ you that I am not going  _ anywhere _ . All right?”

“...You better not break that fucking promise, ol-” Hidan falters. “Kakuzu.” He returns to the bed, curling up in Kakuzu’s arms like they’re a lifeline, and growls, “Or I’ll drag you back from hell myself.”

***

It gets worse, over time. 

It gets worse, it gets worse, it gets worse, and when Hidan wakes up with Kakuzu holding a kunai to his throat and demanding to know who he is and where they are, he makes up his mind then and there to drag Kakuzu to Pain and Konan first thing in the morning. If they’re the fucking leaders, then they are  _ going  _ to help Kakuzu find some back-alley doctor to visit, since Jashin knew the old man would never go to a  _ real  _ one.

“Man, what the fuck?!” Hidan snarls, trying to reach for his scythe but pausing when the pressure of the blade against his throat increases. “Ha! Just try it, fucker, you  _ know  _ it won’t work.”

“I won’t  _ ask  _ you  _ again _ .”

“We’re in fucking - the Rain Village! The hideout! Where  _ else  _ would we be? You sleepwalking or some shit?!”

“Don’t play games with  _ me _ , you who-” As Kakuzu speaks, he draws his free hand back to strike. The tentacles come out of his wrist on instinct, and he - stops talking, stares at them, horrified, and drops the kunai from his other hand.

Hidan takes the opportunity to kick free and lunge out of the bed, grabbing his scythe and rolling into a defensive stance as he does so. There’s a moment of tense, terrible silence, before Kakuzu finally addresses him.

“H...Hidan.”

“Yeah, no shit! What were you about to call me, a  _ whore _ ? Real fucking nice,  _ jackass _ . I love you, too. Really, I do.”

“I-I thought I was-”

“Thought you were, what, with a hooker or some shit? Didn’t recognize me? Or this room? Is it too dark in here for your old fucking eyes? Do you need glasses, shitface?” The venom spews forth from Hidan in increasingly  _ louder  _ tones, and he won’t be surprised if one of the other members pounds on their door. Nor, he thinks, will he care.

“I thought I was -”

And Kakuzu looks - confused. Deeply, deeply confused, and Hidan, hesitating, lowers his scythe, if not his voice. “What the  **_ fuck  _ ** is going  **_ on  _ ** with you, man?”

“I thought I was - in the Waterfall Village again. My wife-” He swallows, thickly. “My  _ late  _ wife. I was looking for her, and I saw you, and I didn’t know why I would be with someone who wasn’t my wife.”

(Hidan hadn’t known Kakuzu was a widower. He doesn’t like that this is how he found out.)

“And - I thought-” Kakuzu presses his face in his hands, swears quietly under his breath. “I don’t know.”

“...Can I come over, or are you gonna maul me again?” Hidan asks, voice sour.

When he gets no response, Hidan sighs and takes the risk, affection creeping into his tone, even as he tries to keep sounding angry. “You’re going to a doctor tomorrow, fuckface, because I’m not putting up with your bullshit anymore. Okay?”

“Okay.”

“We’re gonna figure out what’s going on in that brain of yours, and then I’ll have my partner back. We can go back to collecting your precious bounties, too. Haven’t done  _ that  _ in a while. That sound fun?”

“Hmmm? What are you talking about?” Kakuzu murmurs, as Hidan draws him into a hug. “We haven’t been ordered to collect any bounties.”

Hidan’s blood runs cold, and after Kakuzu falls asleep, Hidan spends the rest of the night doing prayer rituals and begging Jashin to tell him how to help his partner.

***

Kakuzu takes the diagnosis better than Hidan does. In fact, while Hidan demands to know why there isn’t a cure, threatens and cajoles and curses and clutches his rosary, Kakuzu - says nothing at all. 

***

Curled around each other that night, Hidan murmurs, “I’m not gonna leave you, you know,” and Kakuzu, barely above a whisper, says, “I know.”

***

Konan is the treasurer, now, and Kakuzu doesn’t really go on missions that much anymore, in part because he seems to have lost the drive for it, in part because his health won’t allow for it, even with treatment to slow the progression of his symptoms. 

_Hidan_ has to go, though, because he still needs sacrifices. Because Pain and Konan haven’t fired him or his partner, and so he finally feels like he owes the two of them  _ something _ . 

Usually, he tags along with Deidara and Sasori, when he’s sent out on an assignment. Well, them or Zetsu. He’s a third-wheel, either way, until Pain recruits Tobi, but Hidan and Tobi don’t have the natural teamwork that Hidan and Kakuzu had, and so Hidan and Tobi end up bouncing between partners - one with Zetsu, one with the artists, and switch.

Soon, the only permanent duos are Pain and Konan, and Kisame and Itachi, because Hidan, Tobi, Zetsu, Deidara, and Sasori have decided to just pair off based on the requirements of their missions. Hidan doubts the leading pair will ever split, but he can’t help but wonder if Kisame and Itachi will eventually begin to mix and match, too, and it hits Hidan that the hideout has become more of a permanent homestead than a temporary resting spot for the lot of them.

For once, the whole group - all ten of them, eleven if Zetsu counts as two - feels like a family.

Hidan thinks, briefly, about his sacraments, about the rule to “slaughter thy neighbor,” then vehemently denounces it, for who had ever referred to their parents, siblings, roommates, or anything of the sort as their  _ neighbors _ ?

***

Kakuzu is finally telling Hidan about more of his past, but it isn’t in any way Hidan would have preferred to hear about it. He’s been called by all kinds of names, now - old teammates, old mentors. Kakuzu even called Konan by his late wife’s name, once, and then shook his head, muttered, “That wasn’t right.”

(Indeed, in moments of clarity, he apologizes.)

Hidan goes on less and less missions, anyhow, and the old pairs slowly come back together, Tobi and Zetsu officially pairing off, too, now that there’s no extra hands. Hidan doesn’t mind, anyway - Kakuzu’s been prone to wandering, and his fits of confusion seem to lessen when Hidan is nearby, so Hidan prefers to stay with his partner.

Just in case.

(When Hidan needs to leave and perform a sacrifice, one of the Paths of Pain, or - much to Hidan’s surprise, really - Itachi stays by Kakuzu’s side.)

***

“Three masks,” Hidan says, and Kakuzu looks at him, confused. 

“Three masks,” Hidan repeats, pointing to Kakuzu’s back. “Where’s the fourth one?”

Kakuzu’s brow furrows further, and Hidan sits behind him on the bed - something Kakuzu never used to allow - and gently taps them all. “Fire. Water. Wind.” Reaching around, he taps Kakuzu’s chest. “Earth. Where’s the Lightning mask?”

“I- I don’t- I don’t know.”

Hidan’s own heartbeat quickens, but he doesn’t let it show in his face. “Okay. Okay, it’s fine. We’ll find it, okay? No worries. You just stay here, handsome, and I’ll be right back, okay?”

He lets his panic show only once he’s left the room, and he very swiftly enlists Sasori and Deidara into the search, while Konan sits with Kakuzu - the first three people he was able to find. They all rope Tobi in, too, and the four men scour the grounds, searching high and low, Hidan praying to Jashin that the heart had not left the hideout -

As, indeed, it had not. Konan finds it, in Hidan and Kakuzu’s room after all, the remnants of the shattered mask underneath the bed. 

Hidan’s horror must have shown on his face, when Konan calls for the search party and shows them what she found, for Deidara mumbles “You okay, Hidan, hmm?” 

Hidan shakes his head, thanks Konan and Tobi and the artists for their help, waits for them to leave, and then hugs a still-confused Kakuzu around the neck, wondering if “You promised you weren’t going anywhere” is even worth saying, anymore. After all -

Kakuzu’s hearts only crawled off to die when they came to a natural end.

***

The fire heart went next - Zetsu found the mask. Then the wind - Pain, this time.

When all that was left were water and earth, and Kakuzu hadn’t even breathed a word about replacing the others, Hidan started to panic. 

“Hey, wanna go on a walk?” he asks, voice wavering more than he wants it to. “Find some replacement hearts? Earth Grudge Fear some assholes?”

“That technique is forbidden,” Kakuzu hisses, and then, warily, “How does a Shinobi from the Steam Village even know about that?”

_Because we’re in love,_ Hidan thinks, forlornly, but what he  _ says  _ is: “You told me. Remember?”

Kakuzu does not remember, but he mumbles something about not wanting Hidan to leave the room, and so Hidan stays.

***

“I love you,” Kakuzu murmurs, one day, and he hasn’t said it in so long that something in Hidan breaks, and he cries, and he cries, and he cries, Kakuzu holding him close and whispering, “And why are there tears, my Hidan?”

And something in that familiarity - that  _ affection  _ \- makes Hidan cry harder.

***

Rituals get longer. Sacrifices get bloodier. Prayers grow more and more desperate.  _ Don’t let the water heart die. Or, at least, let Kakuzu decide to find spares. Please. Please, Lord Jashin, please. Please do this, for your faithful servant. _

***

One heart left. 

Kisame had looked apologetic, when he’d handed the final mask’s shards to Hidan; Itachi had stood at his partner’s side, face equally mournful. 

“It was in the kitchen,” Kisame had said, “under the table. Itachi and I tried to help it.”

***

Hidan begs Kakuzu to take his heart. Kakuzu asks who Hidan even is. 

Hidan, desperate, presses Kakuzu’s palm to his chest. “It’ll never stop beating. Never. Never, never, never. And it’s already yours, isn’t it? Isn’t it, Kakuzu? Take it. Take it, please. Take it.”

The lack of a reaction sends Hidan into hysterics, desperate cries that he’s sure will draw forth other members.

“Take it! Rip it out of me! Keep it for yourself! Please! Please, Kakuzu-”

“Hidan-”  _ That’s - fuck, he doesn’t even know who it is, just a voice. _ “Hidan, stop-”

“Kakuzu! Please! You’ll die! You’ll die, baby, don’t you understand-” Never, never, has Hidan actually used terms of endearment around the other members of the Akatuski. But he’s also long since decided that he no longer cares about keeping up appearances. “You’ll die, without this, so please, please - my heart- your heart-”

“Hidan,” says the voice again, and he’s still not sure whose it is, if it’s real, if it’s  _ Jashin’s _ , maybe, that shitty fucking god who wouldn’t even grant Hidan his one request, “you don’t really want him to keep  _ living  _ like this, do you?”

“No - No, stop, I want him- Please, Kakuzu, baby, you remember, don’t you? You remember me? Kakuzu? Sweethearts?”  _ Stop with the plural. There’s just one now. No! No, there will be two! He will have mine- mine- _

“...I told you, the day we became partners,” Kakuzu says, suddenly, and there it is - a burst of recognition, for the pet name had triggered something. “I don’t want your heart, Hidan.”

“But you stole it anyway! You stole it, you stole it! So keep it - please, please, please-”

Kakuzu does not take it, and he never calls Hidan by his name again.

***

_ I could turn him into a puppet, or make some in the masks’ likenesses.  
Do you want me to make you some clay figures that look like his masks?  
Do you want me to make you some origami that looks like his masks?  
There will still be a place for you in our new world, Hidan.   
And, at least, with you, he found a place in this one.  
You could plant a garden! Did he even like flowers?  
I know how hard it is to lose who we love, Hidan - to lose our family.  
So does Tobi! _

Hidan stares, mutely, at his - friends? family? family. - as they all try, one by one, to cheer him up. To offer things, to say something, to express their condolences, but all it does is remind him that -

That - 

Nothing will work, and nothing will bring his partner back.

And so, holding his rosary to his chest, he whispers, “I wish one of you would just kill me, actually. Seriously.”

He doesn’t even care that it’s not possible.


End file.
